00361073

Component

http://onlinepubs.trb.org...s/trr/1981/832/832-003.pdf

https://scholar.google.co...rger&publication_year=1981

A case study of the Colorado River at Glenwood Springs, Colorado, is presented to demonstrate several statistical tests for identifying watersheds in which conditions are changing with time. Results of the tests indicate that annual peak flows of the Colorado River are influenced significantly by reservoir regulation. Consequently, conventional methods of frequency analysis are not suitable for obtaining flood estimates from the data series. Time-series analysis is a versatile approach to flood-frequency determinations when conventional statistical methods are not appropriate. The basic strategy of time-series analysis is to treat each value of the regulated annual peak-flow series as a combination of two elements-a deterministic component and a stochastic component. The deterministic component is quantified and removed from the flood series. The residual stochastic components, found to be stationary and independent, are then fitted to a probability distribution from which annual floods are estimated. Results of the time-series analysis show that the 2 percent and 1 percent chance floods, both required for Interstate highway design, are substantially less than corresponding log-Pearson type III estimates. Because the time-series analysis is able to detect and to treat the impact of reservoir regulation on the peak-flow series, the resulting flood frequency estimates are more representative of the watershed. (Author)

Publication of this paper sponsored by Committee on Hydrology, Hydraulics and Water Quality. Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the Transportation Research Board of the National Academy of Sciences. Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved

01411640

pp 12-21

1981

Transportation Research Record

60th Annual Meeting of the Transportation Research Board

0309033098

Print

Figures (9) ; Maps (1) ; References (15) ; Tables (7)

Floods; Reservoirs; Rivers; Statistical analysis; Time series analysis; Watersheds

Flood frequency

Data and Information Technology; Highways; Hydraulics and Hydrology; I26: Water Run-off - Freeze-thaw

TRIS, TRB

Dec 30 1982 12:00AM

• DYNAMICS APPROACH FOR MONITORING BRIDGE DETERIORATION
• EVALUATION OF FILTER FABRICS FOR USE IN SILT FENCES
• FATIGUE CRACKS AND THEIR DETECTION
• PREDICTION OF STORM-INDUCED SEDIMENT YIELD FROM HIGHWAY CONSTRUCTION